Some issues with my alkatronic

Its running ok . Then on 11th Aug 08:26 test start to show zero dkh.
All other tests after 08:26 is show zero dkh.
I check the setting when I am home around 18:30 and found Reference value for both low and high were zero.
and baseline calibration was on.
I did not do any setting change why the reference value and the baseline calibration can change by itself?
0_1534049828948_11082018 graph.png

0_1534049990322_11082018 history.png
Is this normal?

Thank You

I set back the ref high and low and off the baseline calibration after fail to get a dkh reading even I off the alkatronic power and power back 10 minutes later.
After setting back the ref and off the baseline calibration I do a retest and this time I get a kh reading.
Just wonder how the above changing was change?

Not normal, check your tube fittings and also check if the dosing tip is clear.
Best way is to prime the line, as you can see that it is comong out.